The present invention is directed to an improved filtration system for removal of contaminants, particularly, an air driven filtration system used for ventilation and removal of contaminated particulates from hazardous work areas.
When working in a hazardous and confined environment, it is desirable to protect the outside environment and the workers working in the hazardous environment. This invention is particularly useful in areas which require the removal and filtration of large volumes of air from the hazardous work area. Highly contaminated work areas such as removal of asbestos from a building, industrial cleaning, toxic waste removal, confined areas having large accumulations of dust, etc. require the efficient removal and filtration of air to remove the hazardous particulates present in the work area.
Air filtration systems have been used in hazardous work areas for some time. U.S. Pat. No. 4,604,111 to Anthony Natale describes a filtration device and method for removing particulate contamination from a contaminated area. The Natale system establishes a negative air pressure within an enclosed space. The enclosed space is provided with an inlet and an outlet. The filter means is positioned in advance of the outlet so that air is drawn into the enclosed space through the inlet and expelled from the enclosed space through the filter means and out the outlet. A seal means is provided for sealing the inlet against air exiting from the enclosed space to the exterior in the event of loss of negative air pressure in the enclosed space. Other similar type filtration systems incorporating filter mediums have been described in various U.S. Patents and Publications.
The prior art devices, however, have a number of disadvantages which limit their ability to efficiently filter air from areas not specifically designed or falling within a size range adapted to the capabilities of the filtration device. In addition, conventional filtration devices are powered by electric motors which are not suitable for some hazardous environments. For example, in some environments electric motors may present a fire or explosion hazard. In high-temperature environments, electric motors might be adversely affected and not operate properly. Electric motor filtration devices are also preset for operational parameters. Typically, the motor speed will be preset so that an operator may select the motor speed of the filtration system to run at high, medium or low. The speed of the motor will effect the rate at which the filtration device will pull air through the contaminated enclosure. Difficulties may be encountered in matching the filtration system motor speed with the size of the enclosed hazardous area to remove air therethrough at the desired air flow rate.
It is an object of the present invention to provide an air filtration system which is air driven for use in all types of hazardous environments, including high temperature environments and environments which may be susceptible to fire or explosion.
It is another object of the present invention to provide an air drive filtration system having an adjustable air flow rate so that the filtration system air flow rate may be adjusted to the size of the hazardous enclosure to establish an optimum air flow rate through the enclosure.
It is yet another object of the present invention to provide an air driven filtration system including a power module having at least one remote filter pack which may be placed within a contaminated area. The filter pack is connected to the power module by flexible ducting and is completely disposable.
It is a further object of the present invention to provide an air filtration system requiring no cleaning of the contaminated remote filter pack thereby minimizing exposure of the workers to contaminated material.
It is an additional object of the present invention to provide an air infiltration system equipped with remote filter packs enabling the removal and filtration of contaminants in areas which are difficult to access.